Some methods and devices of the prior art assist in authentication of transactions based on secret keys and a count key that end-user can apply to provide the decoded secret validating the transaction. For example, the visual alphanumeric challenges (CAPTCHAs), token validators and visual validations of static images with physical decoding element.
However, there has been a need by banking corporations to attract people to use mobile banking interactions in order to reduce operational costs and enhance customer experience. Moreover, customers are constantly challenged with complicated authentication techniques (e.g., special devices, paper tables, etc. . . . ) and questions about transaction security. Thus, there is an opportunity to introduce new methods for transaction security that are easy to operate, visually attractive and safe. These methods aim to enhance the end-user experience while ensuring the security and the sense of safety.
The patent document EP 0260815 A1, titled: SECURE ENCODING METHOD AND ASSOCIATED PRODUCTS, published on Mar. 23, 1988, proposes a means for producing visual information that can only be retrieved when two random-looking shares are overlaid to each other. This method is the base of what is known in the literature as visual cryptography. The present invention differs from the document EP 0260815 A1 allowing one of the random-looking patterns to be printed on a physical safe card and safely reused in multiple transactions. Additionally, the present invention adapts visual cryptography to authentication contexts extending the concept of visual cryptography to sequential frames (i.e., video), as opposed to static images.
The patent document U.S. 20110026716 A1, titled: METHOD AND SYSTEM FOR ON-SCREEN AUTHENTICATION USING SECRET VISUAL MESSAGE, published on Feb. 3, 2011, presents an authentication method based on visual cryptography for scenarios in which authentication information is encoded into a static video cryptography share, which is transmitted to and displayed on a device and visually recoverable only upon overlaying the correct secret share on the display. The shares are produced through a (m, n) secret sharing scheme process. The present invention differs from this technique in the document U.S. 20110026716 A1 by proposing an efficient share production scheme, as opposed to (m, n) secret sharing and extending the concept of visual cryptography to sequential frames (i.e., video), as opposed to static images.
The patent document WO 2004081870 A1, titled: VISUAL CRYPTOGRAPHY SYSTEM, published on Sep. 23, 2004, introduces a system based on visual cryptography for sharing secrets that relies on two display-equipped devices, which can adaptively change their pixel sizes in order to make secret recovery (i.e., share alignment) easier. The present invention differs from this technique by introducing non-computational physical decoding element (i.e., the safe card), which will be aligned by the user to the device display for secret recovery. In addition, the pattern printed on the safe card may be safely reused in multiple transactions, and extends the concept of visual cryptography to sequential frames (i.e., video), as opposed to static images.
The patent document U.S. 20120284799 A1, titled: VISUAL CRYPTOGRAPHY AND VOTING TECHNOLOGY, published on Nov. 8, 2012, describes a method for applying visual cryptography to voting scenarios. The present invention differs from this technique by adapting the visual cryptography to authentication contexts, as opposed to voting context. Additionally, it allows the pattern printed on the safe card to be safely reused on multiple transactions, and extends the concept of visual cryptography to sequential frames (i.e., video), instead of static images.
The patent document CN 102 658 741, titled: VISUAL-CRYPTOGRAPHY-BASED VISIBLE ANTI-COPYING TECHNIQUE, published on Sep. 12, 2012, employs visual cryptography standards such as copy-detection watermarks, thus taking advantage of the difficulty of reliably reproducing such patterns with traditional copying equipment. The present invention differs from this technique by adapting the visual cryptography to authentication contexts, as opposed to copy-protection. Additionally, it allows the pattern printed on the safe card to be safely reused on multiple transactions, and extends the concept of visual cryptography to sequential frames (i.e., video), instead of static images.
The patent document U.S. 20050044395 A1, titled: SECURE DATA INPUT DIALOGUE USING VISUAL CRYPTOGRAPHY, published on Feb. 24, 2005, proposes a system based on visual cryptography for exhibiting dynamic input dialogs that can only be fully seen through overlaying a secret share on the display. Our invention differs from this technique by adapting the visual cryptography to authentication contexts, as opposed to input randomization. Additionally, it allows the pattern printed on the safe card to be safely reused on multiple transactions, and extends the concept of visual cryptography to sequential frames (i.e., video), as opposed to static images.
The patent document WO 2004055757 A1, titled: KEY SYNCHRONIZATION IN A VISUAL CRYPTOGRAPHIC SYSTEM, published on Jul. 1, 2004, introduces a two-device system for key establishment based on visual cryptography. One of the devices is used for displaying multiple session key shares, which reveal a session key when overlaid with one of the multiple user shares contained in the other device. The present invention differs from this technique by adjusting the visual cryptography to authentication contexts, as opposed to key establishment. Additionally, it allows the pattern printed on the safe card to be safely reused in multiple transactions (thus avoiding the requirement of keeping multiple safe cards, or equivalent complex devices for storing multiple patterns), and extends the concept of visual cryptography to sequential frames (i.e., video), as opposed to static images.
The patent document CN 102 394 751 B, titled: ONE-TIME PAD PASSWORD SYSTEM BASED ON VISUAL CRYPTOGRAPHY, published on Mar. 28, 2012, provides a one-time password system based on visual cryptography for authentication scenarios, which relies on a set of printed shares that can be only used one time each. The present invention differs from this technique by allowing the pattern printed on the safe card to be safely reused on multiple transactions, thus avoiding the requirement of keeping a set of printed shares and extending the concept of visual cryptography to sequential frames (i.e., video), as opposed to static images.
The patent document EP 1,579,380 B1, titled: AUTHENTICATION SYSTEM WITH VISUAL ENCRYPTION USING POLARISATION OF LIGHT, published on Sep. 28, 2005, with priority document EP 02,080,308 of Dec. 16, 2002, introduces an authentication system based on visual cryptography composed of a light polarization device, which can reveal a hidden secret image from within a host image upon overlaying. The overlaying is rotation-based, which means that multiple secrets can be revealed by the same pattern by changing the placement angle. The present invention differs from this technique by requiring that the secret pattern used for the information retrieval to be printed on a cheap transparent sheet or card, as opposed to light polarization devices, allowing the pattern printed on the safe card to be safely reused in multiple transactions without changing the overlaying angle and extending the concept of visual cryptography to sequential frames (i.e., video), as opposed to static images.
The patent document EP 1,509,879 B1, titled: TAMPER-RESISTANT VISUAL ENCRYPTION METHOD AND DEVICE, published on Mar. 2, 2005, introduces a polarization-based method for encrypting visual information. Retrieval is performed by overlaying with different rotation angles. The present invention differs from this technique by requiring that the secret pattern used for information retrieval to be printed on a cheap transparent sheet or card, as opposed to light polarization devices, the scalable video encoding settings for authentication, allowing the pattern printed on the safe card to be safely reused on multiple transactions without changing the overlaying angles, and extending the concept of visual cryptography to sequential frames (i.e., video), as opposed to static images.